/* file-pcap.c * Routines for PCAP File Format * http://www.tcpdump.org/manpages/pcap-savefile.5.html * * Copyright 2015, Michal Labedzki for Tieto Corporation * * Wireshark - Network traffic analyzer * By Gerald Combs * Copyright 1998 Gerald Combs * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. */ #include "config.h" #include #include #include #include #include #include #include static int proto_pcap = -1; static dissector_handle_t pcap_pktdata_handle; static int hf_pcap_header = -1; static int hf_pcap_header_magic_number = -1; static int hf_pcap_header_version_major = -1; static int hf_pcap_header_version_minor = -1; static int hf_pcap_header_this_zone = -1; static int hf_pcap_header_sigfigs = -1; static int hf_pcap_header_snapshot_length = -1; static int hf_pcap_header_link_type = -1; static int hf_pcap_packet = -1; static int hf_pcap_packet_timestamp = -1; static int hf_pcap_packet_timestamp_sec = -1; static int hf_pcap_packet_timestamp_usec = -1; static int hf_pcap_packet_included_length = -1; static int hf_pcap_packet_origin_length = -1; static int hf_pcap_packet_data = -1; static expert_field ei_unknown_encoding = EI_INIT; static gint ett_pcap = -1; static gint ett_pcap_header = -1; static gint ett_pcap_packet = -1; static gint ett_pcap_packet_data = -1; static gint ett_pcap_timestamp = -1; static gboolean pref_dissect_next_layer = FALSE; static const value_string magic_number_vals[] = { { 0xA1B2C3D4, "Little-endian" }, { 0xD4C3B2A1, "Big-endian" }, { 0, NULL } }; void proto_register_file_pcap(void); void proto_reg_handoff_file_pcap(void); static int dissect_pcap(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_) { static const guint8 pcap_magic[] = { 0xA1, 0xB2, 0xC3, 0xD4 }; static const guint8 pcap_swapped_magic[] = { 0xD4, 0xC3, 0xB2, 0xA1 }; volatile gint offset = 0; proto_tree *main_tree; proto_item *main_item; proto_tree *header_tree; proto_item *header_item; proto_tree *packet_tree; proto_item *packet_item; proto_tree *timestamp_tree; proto_item *timestamp_item; proto_tree *packet_data_tree; proto_item *packet_data_item; volatile guint32 encoding; guint32 origin_length; guint32 length; guint32 link_type; volatile guint32 frame_number = 1; nstime_t timestamp; if (tvb_memeql(tvb, 0, pcap_magic, sizeof(pcap_magic)) && tvb_memeql(tvb, 0, pcap_swapped_magic, sizeof(pcap_swapped_magic))) return 0; main_item = proto_tree_add_item(tree, proto_pcap, tvb, offset, -1, ENC_NA); main_tree = proto_item_add_subtree(main_item, ett_pcap); header_item = proto_tree_add_item(main_tree, hf_pcap_header , tvb, offset, 24, ENC_NA); header_tree = proto_item_add_subtree(header_item, ett_pcap_header); proto_tree_add_item(header_tree, hf_pcap_header_magic_number, tvb, offset, 4, ENC_HOST_ENDIAN); encoding = tvb_get_guint32(tvb, offset, ENC_HOST_ENDIAN); if (encoding == 0xA1B2C3D4) { encoding = ENC_LITTLE_ENDIAN; } else if (encoding == 0xD4C3B2A1) { encoding = ENC_BIG_ENDIAN; } else { expert_add_info(pinfo, main_item, &ei_unknown_encoding); return offset; } offset += 4; proto_tree_add_item(header_tree, hf_pcap_header_version_major, tvb, offset, 2, encoding); offset += 2; proto_tree_add_item(header_tree, hf_pcap_header_version_minor, tvb, offset, 2, encoding); offset += 2; proto_tree_add_item(header_tree, hf_pcap_header_this_zone, tvb, offset, 4, encoding); offset += 4; proto_tree_add_item(header_tree, hf_pcap_header_sigfigs, tvb, offset, 4, encoding); offset += 4; proto_tree_add_item(header_tree, hf_pcap_header_snapshot_length, tvb, offset, 4, encoding); offset += 4; proto_tree_add_item(header_tree, hf_pcap_header_link_type, tvb, offset, 4, encoding); link_type = tvb_get_guint32(tvb, offset, encoding); offset += 4; while (offset < (gint) tvb_reported_length(tvb)) { packet_item = proto_tree_add_item(main_tree, hf_pcap_packet, tvb, offset, 4 * 4, ENC_NA); packet_tree = proto_item_add_subtree(packet_item, ett_pcap_packet); proto_item_append_text(packet_item, " %u", frame_number); timestamp.secs = tvb_get_guint32(tvb, offset, encoding); timestamp.nsecs = tvb_get_guint32(tvb, offset + 4, encoding) * 1000; timestamp_item = proto_tree_add_time(packet_tree, hf_pcap_packet_timestamp, tvb, offset, 8, ×tamp); timestamp_tree = proto_item_add_subtree(timestamp_item, ett_pcap_timestamp); proto_tree_add_item(timestamp_tree, hf_pcap_packet_timestamp_sec, tvb, offset, 4, encoding); offset += 4; proto_tree_add_item(timestamp_tree, hf_pcap_packet_timestamp_usec, tvb, offset, 4, encoding); offset += 4; proto_tree_add_item_ret_uint(packet_tree, hf_pcap_packet_included_length, tvb, offset, 4, encoding, &length); offset += 4; proto_tree_add_item_ret_uint(packet_tree, hf_pcap_packet_origin_length, tvb, offset, 4, encoding, &origin_length); offset += 4; packet_data_item = proto_tree_add_item(packet_tree, hf_pcap_packet_data, tvb, offset, length, ENC_NA); packet_data_tree = proto_item_add_subtree(packet_data_item, ett_pcap_packet_data); pinfo->fd->num = frame_number; pinfo->fd->abs_ts = timestamp; if (pref_dissect_next_layer) { TRY { call_dissector_with_data(pcap_pktdata_handle, tvb_new_subset(tvb, offset, length, origin_length), pinfo, packet_data_tree, &link_type); } CATCH_BOUNDS_ERRORS { show_exception(tvb, pinfo, packet_data_tree, EXCEPT_CODE, GET_MESSAGE); } ENDTRY; } offset += length; proto_item_set_len(packet_item, 4 * 4 + length); frame_number += 1; } return offset; } static gboolean dissect_pcap_heur(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_) { return dissect_pcap(tvb, pinfo, tree, NULL) > 0; } void proto_register_file_pcap(void) { module_t *module; expert_module_t *expert_module; static hf_register_info hf[] = { { &hf_pcap_header, { "Header", "pcap.header", FT_NONE, BASE_NONE, NULL, 0x00, NULL, HFILL } }, { &hf_pcap_header_magic_number, { "Magic Bytes", "pcap.header.magic_bytes", FT_UINT32, BASE_HEX, VALS(magic_number_vals), 0x00, NULL, HFILL } }, { &hf_pcap_header_version_major, { "Version Major", "pcap.header.version.major", FT_UINT16, BASE_DEC, NULL, 0x00, NULL, HFILL } }, { &hf_pcap_header_version_minor, { "Version Minor", "pcap.header.version.minor", FT_UINT16, BASE_DEC, NULL, 0x00, NULL, HFILL } }, { &hf_pcap_header_this_zone, { "This Zone", "pcap.header.this_zone", FT_INT32, BASE_DEC, NULL, 0x00, NULL, HFILL } }, { &hf_pcap_header_sigfigs, { "Sigfigs", "pcap.header.sigfigs", FT_UINT32, BASE_DEC, NULL, 0x00, NULL, HFILL } }, { &hf_pcap_header_snapshot_length, { "Snapshot Length", "pcap.header.snapshot_length", FT_UINT32, BASE_DEC, NULL, 0x00, NULL, HFILL } }, { &hf_pcap_header_link_type, { "Link Type", "pcap.header.link_type", FT_UINT32, BASE_DEC_HEX, VALS(link_type_vals), 0x00, NULL, HFILL } }, { &hf_pcap_packet, { "Packet", "pcap.packet", FT_NONE, BASE_NONE, NULL, 0x00, NULL, HFILL } }, { &hf_pcap_packet_timestamp, { "Timestamp", "pcap.packet.timestamp", FT_ABSOLUTE_TIME, ABSOLUTE_TIME_LOCAL, NULL, 0x00, NULL, HFILL } }, { &hf_pcap_packet_timestamp_sec, { "Timestamp sec", "pcap.packet.timestamp.sec", FT_UINT32, BASE_DEC, NULL, 0x00, NULL, HFILL } }, { &hf_pcap_packet_timestamp_usec, { "Timestamp usec", "pcap.packet.timestamp.usec", FT_UINT32, BASE_DEC, NULL, 0x00, NULL, HFILL } }, { &hf_pcap_packet_included_length, { "Included Length", "pcap.packet.included_length", FT_UINT32, BASE_DEC, NULL, 0x00, NULL, HFILL } }, { &hf_pcap_packet_origin_length, { "Origin Length", "pcap.packet.origin_length", FT_UINT32, BASE_DEC, NULL, 0x00, NULL, HFILL } }, { &hf_pcap_packet_data, { "Data", "pcap.packet.data", FT_NONE, BASE_NONE, NULL, 0x00, NULL, HFILL } }, }; static ei_register_info ei[] = { { &ei_unknown_encoding, { "pcap.unknown_encoding", PI_PROTOCOL, PI_ERROR, "Unknown Encoding", EXPFILL }} }; static gint *ett[] = { &ett_pcap, &ett_pcap_header, &ett_pcap_packet, &ett_pcap_packet_data, &ett_pcap_timestamp }; proto_pcap = proto_register_protocol("PCAP File Format", "File-PCAP", "file-pcap"); proto_register_field_array(proto_pcap, hf, array_length(hf)); proto_register_subtree_array(ett, array_length(ett)); register_dissector("file-pcap", dissect_pcap, proto_pcap); module = prefs_register_protocol(proto_pcap, NULL); prefs_register_static_text_preference(module, "version", "PCAP version: >=2.4", "Version of file-format supported by this dissector."); prefs_register_bool_preference(module, "dissect_next_layer", "Dissect next layer", "Dissect next layer", &pref_dissect_next_layer); expert_module = expert_register_protocol(proto_pcap); expert_register_field_array(expert_module, ei, array_length(ei)); } void proto_reg_handoff_file_pcap(void) { heur_dissector_add("wtap_file", dissect_pcap_heur, "PCAP File", "pcap_wtap", proto_pcap, HEURISTIC_ENABLE); pcap_pktdata_handle = find_dissector("pcap_pktdata"); } /* * Editor modelines - http://www.wireshark.org/tools/modelines.html * * Local variables: * c-basic-offset: 4 * tab-width: 8 * indent-tabs-mode: nil * End: * * vi: set shiftwidth=4 tabstop=8 expandtab: * :indentSize=4:tabSize=8:noTabs=true: */